The present invention relates to proximate analyzers, and more particularly analyzers which heat the sample during analysis.
The proximate analysis of a material to determine the content of at least some of its constituent components provides important information regarding the material. This is particularly true with coal and coke, which are composed primarily of the four components moisture, volatiles, fixed carbon, and ash. Coal and coke proximate analysis results are useful in predicting energy content, potential pollution problems, and the ash which will remain after burning.
The ASTM standards for determining the moisture, volatiles, fixed carbon, and ash content of coal and coke are relatively complex. Each of the moisture, volatiles, and ash content determinations are made by first weighing a sample to be analyzed, second subjecting the sample to elevated temperatures in a controlled atmosphere for a standard period of time, and third weighing the sample to determine sample weight loss. Well-known mathematical formulas are then utilized to calculate the moisture, volatiles, fixed carbon, and ash content of the material. The samples must be repeatedly handled and weighed during testing. The handling is time consuming and can be dangerous because of the high temperatures involved. Further, because the sample must be left in the furnace for a fixed period of time, the tests are relatively time-consuming with no provision made for rapidly analyzing a sample analyzable in less then the standard time periods.
Although analyzers have been developed for facilitating the proximate analysis of coal and coke, these analyzers are not without their drawbacks. One such analyzer includes a furnace and a balance having a weigh platform positioned in the furnace. Consequently, a sample, or sample-containing crucible, may be placed on the balance to provide a constant readout of sample weight during the heating period. However, only one sample may be analyzed during each analyzer cycle. Another device includes a rack containing a plurality of samples, or sample-containing crucibles, and a furnace in which the rack is positioned. Although this analyzer is capable of heating a plurality of samples simultaneously, the individual samples must be handled and weighed outside of the furnace both before and after heating.